Deserts, Dinosaurs and Volcanoes British Isles: A Natural History

Once in a while you get an offer you can't refuse.

It's every schoolboy's dream.

Biggles was never like this.

Nearly ready! No point going unless you're fully equipped...

inflatable trousers...

all purpose cutting tool... and most vital of all...

sick bag.

So long, Ground Force, hello...

Air Force. Oooohhh!

From up here you can appreciate how wonderful our landscape is.

I'm also on a mission to explore the past.

We're doing about 600 miles per hour.

At that speed I can get from London to the tip of Scotland in about an hour.

But in that same one-hour flight, I am also making another journey,

one that crosses the entire history of our islands.

Every landscape that's flashing by beneath me

has been shaped over millions of years by momentous events!

So if you want to know why Britain looks the way it does, then hang on.

You're in for one heck of a ride!

We've been blown apart by volcanic explosions.

Our islands have been raised up into peaks as high as the Himalayas.

We've been part of a desert bigger than the Sahara,

and submerged beneath great oceans.

We've been cloaked in rainforests,

and even had our very own Jurassic Park!

Our landscape is littered with clues that both reveal our past

and explain our present.

They'll guide me on this journey to uncover the origins of the British Isles.

Those are the Outer Hebrides down there,

and that's where our story begins.

The Isle of Lewis is one of Britain's wildest, most remote places.

This place feels ancient,

and it's where the connection between landscape and the underlying rock is laid bare.

These are the standing stones of Callanish.

They were raised 5,000 years ago, making them old enough

to pre-date the pyramids of Ancient Egypt!

The earliest settlers here used the local rocks to build this spectacular monument.

Part ceremonial, part calendar, these stones were used

to chart the passage of the sun, moon and stars across the sky...

a kind of ancient farmer's almanac.

This ancient timepiece has been tracking the seasons for generations,

but the rock it's made from records events from a more distant past.

5,000 years seems like a long time,

but it's the blink of an eye compared with the age of the stones.

They're the real reason I'm here.

They've been on a remarkable journey through time.

These rocks are nearly three billion years old, by far the oldest things in Britain.

They were created at a time when the whole planet was in a state of flux.

The map of the world would have been totally unrecognizable.

Even half a billion years ago, the British Isles didn't exist.

For a start, Scotland and Ireland were near the equator while England and Wales were near the South Pole!

But powerful forces deep within the Earth were carrying these pieces

steadily towards each other at just a few centimetres each year.

Until finally, somewhere south of the equator, these pieces crashed together.

HELICOPTER ENGINE WHIRS

This is where they met!

That's the Scottish chunk,

and England down to the south.

The join itself is buried hundreds of metres below the moorland peat,

but it runs alongside a far more obvious and famous boundary between North and South -

Hadrian's Wall.

When Hadrian built the wall almost 2,000 years ago,

he had no idea how important this place was in Britain's history.

But if you know where to look,

there are signs all over the British Isles of the monumental events

that accompanied this first "act of union" between England and Scotland.

And some of the most impressive are north of this border, among our highest peaks.

The Scottish Highlands.

This landscape is just about as untamed as Britain can get.

Our last true wilderness.

This is Aonach Mor, in the heart of the Highlands.

It's a Munro - one of the 280 peaks in Scotland that rise above 3,000 feet.

They're named after an Edwardian mountaineer, Hugh Munro, who was the first to record them...

and climb them.

He must have been a tough guy.

But the mountains beat even him.

Sadly, Munro died just two summits short of his goal of conquering them all.

Here's the cairn.

This must be the very top. There we go. Aonach Mor!

My first Munro!

Only to 279 go.

From up here they all look big,

right from the Cairngorms across to Aonach Beg that one with the snow cap on there.

These mountains here above Glencoe, they must all be Munros.

And there's the daddy of them all... Ben Nevis.

Britain's highest mountain.

1,344 metres.

For old-fashioned chaps like me -

and for Mr Munro's benefit - that comes to exactly 4,408 feet.

The name Ben Nevis comes from the Gaelic for "Mountain of Heaven".

On a day like today, it certainly feels as though I've climbed towards the gods.

When first formed, the peaks would have been even more impressive.

They were once tens of thousands of feet high,

forming a range of mountains as tall as the Himalayas.

Ben Nevis would have rivalled Mount Everest!

The Highlands mark a kind of "crumple zone" forced upwards

as England and Scotland crashed into each other.

And all along the southern side of this join, huge volcanic eruptions

created Snowdonia and the Lake District.

So what happened to Scotland's Himalayas?

Where are they now?

As soon as they were formed, they came under attack... from the weather!

Snow and ice, wind and rain

all began to eat away at the rock, cutting these giants down to size.

THUNDER CRACKS

And today,

400 million years later, this attack is still raging.

Nowhere has more "weather" than Scotland -

900 billion gallons of rain falls here each year

and it all collects in thousands of streams and rivers,

gaining strength and gathering momentum as it goes.

Then, gravity takes over, and as everybody knows, gravity is irresistible.

These powerful rivers gouge away at the land as they pour down the mountainside,

cutting and constantly re-shaping what's left of the Highlands.

And the biggest Scottish river is this one - the Tay.

It's over 100 miles long, and by the time it reaches the sea,

it's carrying more water than the Thames and Severn combined.

The water in this river has come from all over Scotland.

It all gets funnelled into this one valley.

Nothing can resist its power for long, as it pummels and pounds everything in its path.

And I know just how that feels!

Some water feature!

Whoo!

Like going through the washing machine and the wringer in one go.

For hundreds of millions of years,

the weather has slowly taken the mountains apart.

And the rivers have spread their remains far and wide.

Today, Scotland's Himalayas have been worn almost flat.

But where has all that rock gone?

Well, a lot of it ended up here, and built this...

Stanage Edge in Derbyshire. It's all millstone grit,

made from the pulverised remains of those ancient Scottish mountains.

Today it's part of the Pennines,

which means that the very backbone of England was made in Scotland!

Grit stone is tough stuff,

and full of sharp edges, making it perfect for one job.

For hundreds of years, maybe back as far as the 12th century,

millstones have been quarried from this exposed escarpment.

And the surprising thing is, you can still find them today

scattered like handfuls of coins right all along this ridge.

There are around 1,500 of them dotted about the place.

At two tonnes apiece, these were used for turning grain into flour.

There are smaller ones as well - grindstones -

used for giving Sheffield cutlery its cutting edge.

But the grit stones make it hard to carve out a living up here.

On these bleak moors, even the plants have it tough.

The soil here is badly drained and extremely boggy...

-SQUELCH

-It is!

Clumps of cotton grass break up the great swathes of heather and bracken.

It's all pretty desolate and yet, if you look a bit closer,

there are botanical treasures to be found...like the sundew.

Its rounded leaves are covered in hairs,

each one of which is equipped with sticky goo.

It catches insects to supplement its diet.

The landing's easy, but the taking-off is nigh-on impossible.

Just one insect can provide enough nutrients to keep this sundew going for months.

The Pennines stretch for over 200 miles from Derbyshire all the way to the Scottish border.

This place is very close to my heart.

Some of my earliest memories are of family trips up here.

And I guess it's the same for many.

I was brought up on these Yorkshire gritstones, and it was journeys

up on to the moors that first fired my love for this landscape.

These moors are surrounded by some of our largest cities,

providing a place to escape from the hurly-burly of modern life.

But nestling beneath the Yorkshire Moors is a very different countryside -

softer, greener and more fertile.

The Dales.

This is limestone country, and here, again, the rock has been used to great effect.

Swaledale is criss-crossed by walls made from the local stone.

But you can also use this stone to build something else -

a picture of the Dales' past,

revealing an event that shaped the British Isles.

The stones are literally filled with clues.

But you've got to rummage a bit

until you find

what you are looking for... Here's one, there we are.

It's a fossil coral.

But what's a coral doing in the Yorkshire Dales?

Corals like this only grow in warm, shallow water.

Today, they thrive on the reefs of Australia and the Caribbean.

Their fossilised presence here can only mean one thing

there must once have been a tropical reef right here in Yorkshire.

You can find fossil corals in Ireland, southern Scotland, the Lake District and Somerset.

So these ancient tropical seas

must have covered much of the British isles.

This landscape is more like the surface of the moon than the Yorkshire Dales.

It's a limestone pavement.

Great lumps of rock that interlock like a jigsaw with great fissures in between them.

The lumps are called clints, and the fissures are called grikes,

some of which are three or four metres deep, so don't lose your footing!

This landscape has been created by water.

It dissolves limestone, sculpting it into these convoluted shapes.

But there's hardly a stream or river to be seen.

So where are they?

-Ready?

-Ready!

Let her go!

This is where one of those rivers has gone...

Gaping Gill. One of the largest caves in the British Isles.

Wood anemones and wood sorrel...

Oh, but now, nothing - just blackness and shiny rock...

I see mist coming down, and now it's widening...

A great cavern with black walls running with water...

And now the water's running on me! Ah!

Even more scary. Are we there?

Am I there? Is that the bottom?

Ooh! It's like the journey to the centre of the Earth.

That was unbelievable! I've followed the water all the way down.

It's like being a pebble thrown into a waterfall.

And it's the longest unbroken waterfall in Britain

at 111 metres, that's twice the height of Niagara.

And boy, did it feel like it?!

There are several of these monstrous plumes of water

tumbling down through the rock here and they make a heck of a din.

Over hundreds of thousands of years,

they've worn away the limestone to make this enormous cavern.

And how do we know it's limestone?

Because just like the dry stone wall, it's got fossils in it.

There's the coral and down here sea shells, proving this was once underwater.

And when it floods and the water in here rises 10 metres higher than my head, it's underwater again.

The tropical seas that submerged Yorkshire for 30 million years eventually receded.

As our ancient coastline emerged, a new landscape was born.

If you live in Glasgow, you can nip down to the local park to see what happened.

Victoria Park is full of trees - well, stumps.

But they are 300 million years old, and made of stone.

Judging by the size of these stumps, some of the trees must have been 100 feet tall.

And what's more, they were lepidodendrons, trees only found in ancient tropical rainforest.

Britain's ancient rainforest was filled with botanic wonders,

and ruled by insects.

Dragonflies filled the air, and some were huge,

with a wingspan of nearly two feet.

WINGS FLUTTER RAPIDLY

And there were giant millipedes, six feet long.

But these forests left behind more than fossilized insects and tree stumps.

Their real legacy fired one of the greatest revolutions in our history.

It was this...

coal!

This is the Stobswood open cast mine in Northumberland.

It's the largest mine of its kind still operating in Britain,

producing almost a million tonnes a year.

You need massive machinery to dig a hole this big.

This one's called the "Ace of Spades".

The bucket is the size of a family house.

But this huge hole wasn't entirely filled with coal.

The valuable stuff is in these seams,

sandwiched between sandstone and shale.

And there's the clue as to how wood turns into coal.

Each band of grey rock marks a time when these forests were flooded by rising seas

and buried by sand and sediments.

As this built up, the increasing weight slowly compressed the fallen trees of the forest,

transforming them into coal.

It takes a 30ft layer of wood to produce just 3ft of coal...

so just one seam represents a lot of rainforest and an awful lot of time!

Multiply that by each coalfield in Scotland, England and South Wales,

and it shows just how vast the forests were.

Because ancient Britain sat on the equator 300 million years ago,

we had the right conditions to grow the raw materials that would fuel the Industrial Revolution.

But nothing lasts forever.

The British Isles were about to get a shake-up...

a chain of events began that would see the tropical forests disappear,

that would create a beautiful part of the country

and, eventually, some of our most productive land.

Time to head to the Southwest.

Those are the Isles of Scilly down there, 28 miles off Land's End.

They might look like the Bahamas in summer,

but come winter, these islands and headlands take a pounding from the Atlantic.

They are made of granite and we're lucky all this hard rock ended up where it did.

It's the perfect breakwater.

Without it, there wouldn't be anything between southern England

and the fierce Atlantic storms.

If this barrier wasn't here, Cornwall might be a bit smaller.

The Scillies are just the most westerly part of a chain of granite outcrops.

They run through Land's End, Bodmin Moor and up on to Dartmoor.

Here, they've been slowly sculpted into some of our most recognisable landmarks...

..the Dartmoor tors.

But where's all this granite come from?

Where there's granite, there was once molten rock.

These tors are the remains of a huge dome of this magma that sat like a boil beneath our ancient skin,

cooling, slowly, deep underground.

There must have been massive volcanic activity at the time. What was causing it?

50 miles away, the coast of North Devon has some of the answers.

The cliffs at Hartland are made from layer upon layer of ancient sea floor.

These rocks were all laid down horizontally, as you might expect on the seabed,

but they've been dramatically re-arranged. Now they're vertical! So what happened here?

Ooh! That was amazing!

These rocks here have been concertinaed,

the horizontal layers ruptured and buckled into a crazy jumble.

Now, that can only happen under immense pressure,

the sort of pressure you get when continental plates meet.

and that's exactly what happened here as Southern Britain crashed into Continental Europe.

Collisions like this were going on across the globe

and out of the wreckage emerged one single landmass - a supercontinent called Pangaea -

and we were slap bang in the middle of it!

Left sitting near the equator, and basking in the intense heat, Britain got drier and drier.

Lush, tropical Britain became a desert!

And the greatest token of this desert past lies in a most unexpected place.

Devon, glorious Devon - a county that's crisscrossed by sunken lanes,

like this one at Pitt Farm.

Cows have been herded up and down this from pasture to milking parlour for centuries.

Go on!

They got a shift on, didn't they?

Devonshire's cows are lucky. The rolling fields here are really special.

Just look at this grass - rich, thick and tantalisingly sweet.

It almost makes you wish you were a cow! As any horticulturist knows

you only get growth like this when you've got decent soil.

There we are. Look at that - a gardener's dream

and an important legacy of our desert past.

This distinctive red colour comes from the iron in the underlying desert rocks

that's slowly been broken down to form this soil.

It's strange to think that this, some of our most fertile land,

owes its origins to one of the harshest periods in our history.

And with grazing this good, it's no wonder these cows are so productive.

Here on Pitt Farm, each one of these girls produces about five gallons of milk every day!

And this is where much of the Devon grass goes...into clotted cream.

In my humble opinion, one of the greatest contributions Britain has made to the civilized world.

But there is one contentious point.

Is it jam first

and then cream?

Mmm, that's very, very good.

Or is it cream first and then jam?

Oh, it's very difficult. It clearly requires...

..considerable research.

I've got the time, the inclination, the clotted cream.

It is very nice with the jam first.

You get the strawberries coming through...

Thank you. It was very nice. Mm!

You wouldn't have a glass of milk, would you?

You can have too much of a good thing, you know.

And the conclusion is...

..inconclusive.

One thing is for sure.

After 80 million years of baking heat, the deserts began to disappear.

Britain was back on the move.

We were about to enjoy a much balmier time,

and to find out more, I need to visit our very own Jurassic coastline,

that stretches the width of Dorset, from Lyme Regis to Swanage.

All along this coast, the sea is eating away at the cliffs,

uncovering clues and scattering them on the beach.

Every pebble under your feet could be 200 million years old.

Rocks like these can tell us a huge amount about that time

and even amateurs like me can find out. Watch this.

Wow! Look at that...

an ammonite.

This animal didn't live in the desert, but in the sea.

The supercontinent was breaking up and we inherited some superb beachfront real estate.

Our south coast would have been like the Caribbean.

These Jurassic seas weren't just filled with ammonites,

they were home to all kinds of fantastical creatures.

For the next 70 million years,

Britain was a tropical paradise of inviting lagoons and endless reefs.

In these clear, warm waters, a new piece of the British landscape was being created.

Just as in Yorkshire, millions of years before,

this new landscape is made of limestone.

It sweeps in a great arc across Middle England,

from the Dorset coast, along the Cotswolds, up to Lincolnshire.

It's easy to follow its path today, because this beautiful stone has been quarried for centuries

and used to build quaint cottages and city halls from Portland to Ashby-cum-Fenby.

BICYCLE BELL TINKLES

The heart of Oxford is built from this butter-coloured stone,

ornately carved and sculpted as any work of art.

All this is made from local Jurassic stone

quarried from no more than a few miles away.

Over there is the Bodleian Library.

They've been entitled to receive a copy of every book printed in the UK since 1610.

They might have mine!

But I'm not here to look at the books, I'm here to inspect the walls.

Look at these blocks of stone -

strong, smooth and durable.

Stonemasons called it freestone, not cos it was cheap,

but because it was free of flaws and you could cut it in any direction. But that's not all.

You see, not only is this Jurassic rock strong enough to be used as building blocks,

it's also malleable enough to be intricately carved.

It's the perfect combination.

You only have to come to Oxford on a day like this

and it becomes perfectly obvious why they call it the City of Dreaming Spires.

The masons decorated the buildings with mythical Greek heroes,

rich benefactors,

grotesques and gargoyles.

But little did they know the rock itself held creatures

more monstrous than any gargoyle.

And as the quarrymen dug deeper, more secrets were revealed -

the bones of a giant animal.

It was 25ft tall, weighed about a ton,

stood on two legs.

It was a dinosaur!

Since these first discoveries, hundreds of dinosaurs have been found in our limestone rocks.

The British Isles really was the original Jurassic park.

But while this period was known as the age of the dinosaurs,

it also marks the arrival of another great group of living things -

flowering plants like this magnolia, which is one of the most primitive.

Its ancestors first opened their cup-shaped blossoms

when the dinosaurs were still about, around 100 million years ago.

I'm glad it was the dinosaurs that died out and not the flowers.

Throughout this time, dinosaurs ruled

from the Isle of Wight to the Isle of Skye.

SCREECHING

Then, around 100 million years ago,

all traces of these magnificent creatures disappeared from our shores.

It coincided with the greatest event to effect our islands,

and it left us with perhaps the most famous lumps of rock in the world.

I'm on my way to see them now.

The Seven Sisters on the Sussex coast - one of our most spectacular landmarks.

This is by far the best place to see them.

They have welcomed home-comers and repelled invaders for centuries,

but their history goes back much further than that.

And to discover it, I need to take a closer look.

Apart from these layers of flint that are embedded in it, this chalk has no distinguishing features,

nothing to give a clue as to its origins, at least, not to the naked eye.

But put it under an electron microscope and it comes alive.

These are the shells and skeletons of tiny sea creatures, trillions of them!

This whole cliff is one huge fossil bed.

And that can only mean one thing. 100 million years ago,

Britain was covered by water, not just by a few feet of it.

Then the sea level was 300 metres higher than it is today.

The shallow Jurassic sea rose to cover the land.

Virtually all of Britain vanished beneath the waves and with it went our dinosaurs.

The British Isles were to remain at the bottom of the deep for the 30 next million years,

until one last mega-event forced them back up to the surface.

The best place to see what happened is on the north coast of Northern Ireland.

What I'm looking for was created as Britain neared the end of an epic journey across the globe.

Just 60 million years ago, Britain was drifting towards its present position.

A journey that had taken it 8,000 miles since England and Scotland

had first come together south of the equator.

And there it is.

The effect on the land couldn't be more eye-catching.

Rising up out of the sea on the Antrim coast

is a seemingly man-made playground of stepping stones,

over 40,000 hexagonal columns.

This has to be one of the oddest place I've visited on my travels through the British Isles.

It's the Giant's Causeway.

Local legend has it that an Irish giant named Finn McCool was responsible for all this lot.

He was challenged to a contest of strength by another giant living on the Scottish island of Staffa,

just 80 miles over there.

So Finn hurled rocks into the sea...

..building a causeway, so he could reach his challenger and teach him a lesson.

In truth, the Causeway has a less romantic, but equally violent history.

The columns were formed when lava exploded onto the surface and rapidly cooled.

But these eruptions were on a vast scale effecting not just Ireland but Western Scotland too.

This lava formed most of the Isles of Skye and Mull and the Isle of Staffa,

where you can still see the same hexagonal columns as the Giant's Causeway,

here stacked around Fingal's Cave.

What was causing all this upheaval?

Something that fundamentally changed the nature of the British isles - the birth of the Atlantic Ocean.

The Atlantic is so all-embracing, it's difficult to imagine it not being here.

But for much of our history, it simply didn't exist

and Western Europe nestled up snugly against North America and Greenland.

But as the two continents began to tear apart,

spewing out thousands of miles of lava,

it drove a powerful wedge between the European and North American plates,

slowly forcing them further and further apart.

So 60 million years ago, the Atlantic Ocean was born

and it's still growing today, albeit slowly, about the rate our fingernails grow.

It's already 3,000 miles wide

and increasing by two and a half inches every year.

As the Atlantic opened,

Britain once again slowly emerged from beneath the murky waters...

..but we came up tilted at an angle,

the North first and the rest following over millions of years...

slowly revealing more and more of our foundations.

After the great events that created these foundations,

they would now be shaped by wind,

water, ice and ourselves

into landscapes we recognise today.

The last part of the British Isles to emerge from beneath the Atlantic was the southeast corner.

That makes the rocks here, under England's capital city, some of the youngest in the land.

For the time being, this marks the end of my journey.

But the geological clock that began ticking on the Isle of Lewis

nearly three billion years ago is still going strong.

All around Britain, new rocks are being made

and some day, that mud down there at the bottom of the Thames

will become the next layer of bedrock that underpins our islands

and it's that bedrock that ultimately shapes the very nature of the British Isles.